У меня ваш проект не получилось запустить. Попробуйте так: 
 Code
String filename = "baza.mdb"; 
 if(!FileExists(ExtractFilePath(Application->ExeName)+filename)) 
 { 
 AnsiString ds = "Файл базы данных не обнаружен \n\n\t" +filename; 
 ShowMessage(ds); 
 } 
 else 
 { 
 String WayToBase=ExtractFilePath(Application->ExeName)+filename; 
 ADOConnection1->Connected = false; 
 ADOConnection1->ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;User ID=Admin;Data Source="+WayToBase+";Mode=Share Deny None;Jet OLEDB:System database="";Jet OLEDB:Registry Path="";Jet OLEDB:Database Password="";Jet OLEDB:Engine Type=5;Jet OLEDB:Database Locking Mode=1;Jet OLEDB:Global Partial Bulk Ops=2;Jet OLEDB:Global Bulk Transactions=1;Jet OLEDB:New Database Password="";Jet OLEDB:Create System Database=False;Jet OLEDB:Encrypt Database=False;Jet OLEDB:Don't Copy Locale on Compact=False;Jet OLEDB:Compact Without Replica Repair=False;Jet OLEDB:SFP=False;"; 
 ADOConnection1->Connected = true; 
 ADOTable1->Active = true; 
 ADOTable1->Open(); 
 }